It is known that, in the biosynthesis of androgen in vivo, steroid C17,20-lyase acts at the final stage. That is, steroid C17,20-lyase converts 17-hydroxypregnenolone and 17-hydroxyprogesterone derived from cholesterol to dehydroepiandrosterone and androstenedione, respectively. Therefore, a medicine having steroid C17,20-lyase inhibitory activity suppress the formation of androgen and estrogen which is produced from androgen, and is useful for the preventing and treating diseases whose exacerbation factor is androgen or estrogen. As the disease whose exacerbation factor is androgen or estrogen, there may be mentioned, for example, prostate cancer, prostatic hypertrophy, virilism, hirsutism, male pattern alopecia, precocious puberty, breast cancer, uterine cancer, mastopathy, uterus myoma, endometriosis, adenomyosis of uterus, polycystic ovary syndrome, etc.
It has been already known that some steroid type compounds and some non-steroid type compounds inhibit steroid C17,20-lyase. The steroid type compounds are disclosed in, for example, WO 92/15404,WO 93/20097,EP-A 288053,EP-A 413270, etc. As non-steroid type compounds, for example, (1H-imidazol-1-yl)methyl-substituted benzimidazole derivatives are shown in Japanese Published Unexamined Patent Application No. 85975/1989, carbazole derivatives are shown in WO94/27989 and WO96/14090, azole derivatives are shown in WO95/09157, and 1H-benzimidazole derivatives are shown in U.S. Pat. No. 5,491,161.
Heretofore, steroid C17,20-lyase inhibitors which can actually be used as medicine have not been known. Thus, it has been expected the early development of steroid C17,20-lyase inhibitors which are useful as medicine.